In addition to these key terms, Rackspace Metrics uses some of the key concepts
that are also applied to Cloud Monitoring. For more information, see the
Rackspace Monitoring Concepts
section in the Rackspace Monitoring documentation.

Annotations provide additional insight into numeric metrics. Annotations are
used to highlight specific change events and provide additional information
about these events. Annotations are displayed in Grafana, providing additional
details about specific events and changes on a graph. Rackspace Metrics
provides API operations to submit annotations and to retrieve them from the
Rackspace Metrics database.

Data granularity defines the increments at which metric data is
measured. When you fetch metrics data points by using the Rackspace Metrics
API, you specify several parameters to control the granularity of data
returned:

A time range for the data points

Either the number of data points to return or the resolution of the
data to return

Rackspace Metrics supports the following granularities of data: full
resolution data and rollups computed at 5, 20, 60, 240 and 1440 minute
intervals.

When you query by points, the API selects the resolution that will
return you the number of points that you requested. The API assumes a
30-second frequency, performs the calculation, and selects the
appropriate resolution. For more information, see the Data
granularity
section in the Rackspace Monitoring documentation.

To ingest is the process of obtaining, importing, and processing data for
later use or storage in a database. This process can involve modifying
individual files by editing their content and/or formatting them to fit into a
larger document.

A metric is a measurement of activity or state on a monitored resource.
Checks gather metrics and send them to the monitoring system. Based on
your configurations, a set of metrics might trigger an alarm, causing a
notification to be sent. Metrics can also be used to create graphs. For
more information about metrics, see the
Metrics
section in the Rackspace Monitoring documentation.

A metric series is a named set of data points. A series is identified by a
unique name, which is composed of elements separated by periods that are used
to display the collection of series in a hierarchical tree. For example, a
series that stores the system load average on a server called apache02 in
the DFW data center might be named dfw.servers.apache02.system.load_average.

The query node handles incoming HTTP-based queries, returning raw or aggregate data
for a given time period. It exposes the Query API, which enables users to submit
queries to the Rackspace Metrics database by using a set of query parameters.

The resolution is the number of seconds per data point in a metric series.
Series are created with a resolution which determines how often a data
point can be stored. This resolution is represented as the number
of seconds in time that each data point covers. A series that stores
one data point per minute has a resolution of 60 seconds. Similarly,
a series that stores one data point per second has a resolution of 1
second.

After signing up for the service, a user of Rackspace Metrics can push
captured measurements to the system through the Ingest API over one of
the supported protocols. After a period of time ranging from minutes to
years, the user can use the Rackspace Metrics Query API to retrieve data to
perform tasks such as data analysis and troubleshooting.